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Wind and solar have variable output, so they need to be partnered with flexible power generation. Nuclear is fundamentally inflexible because you can't quickly ramp up or down electricity output from a nuclear power plant.
See this short video for a nice explanation of the incompatibility:
http://www.ilsr.org/coal-nucle... [ilsr.org]

You could vary price of the energy depending on the time of day. Factories would then align energy usage to peak production hours. You always have a few nuclear reactors giving you a baseline of power.

I am not sure how you would regulate consumer usage at 6-7pm, when it is highest. If you can figure out how to store it for a few hours, you will make bank.

Average losses from line loss is 6.6%, so I think that 30% would be a worst of the worst case scenario, something indicating that the grid is operating under abnormal circumstances that are normally avoided. For example, if Fairbanks suffers a generator failure, there's a feeder line to gain power from Anchorage.

Roughly speaking, any power generation system is going to put the necessary transmission systems in to keep losses to under 2%. Even a thousand kilometer transmission line should be under 7% [stanford.edu] East Coast to West Coast is about 4.5k km.HVDC [wikipedia.org] is even better at only 3.5% per 1k km. So you're only looking at 16% for transmitting power from one coast to the other for use.

That is actually done to a very large extent now. Foundries running electric arc furnaces or induction furnaces only run in the off-peak period, currently at night. This artificially increases base loads.

The problem with trying to match generation with demand is that you still have a transmission/distribution problem. Distributed generation is the only way to really solve that, and again economics make it difficult to distribute power generation to the point where local demand is matched to local production in both capacity and timing.

People are trying to get closer to this-- automated demand response can help a little bit.

The California ISO is pretty open with information. They track [caiso.com] daily anticipated demand, actual demand, and available capacity. Some actually predict that solar energy that is not time-shifted will become nearly worthless in five years.

You can store the excess output from those inflexible nuclear power plants in a way that it can be released quickly to smooth out spikes in demand.

We do that by (eg.) pumping water uphill to reservoirs then letting it flow downhill through turbines when the adverts come on TV and everybody goes and makes a cup of tea... (or grabs a beer from the fridge, or whatever else they do in the uncivilized world).

The real problems come on cloudy days when there's no wind. On those days you need enough capacity in you nuclear plants to make up the deficit.

A lot of this talk about nuclear power plants or even coal powered power plants being inflexible is nonsense. They are run continuously because this is more energy efficient. However there is nothing stopping you from burning less coal. In France it is common to partially off nuclear power plants [wikipedia.org] during the night:

In France, however, nuclear power plants use load following. French PWRs use "grey" control rods, in order to replace chemical shim, without introducing a large perturbation of the power distribution. These plants have the capability to make power changes between 30% and 100% of rated power, with a slope of 5% of rated power per minute. Their licensing permits them to respond very quickly to the grid requirements.

A lot of this talk about nuclear power plants or even coal powered power plants being inflexible is nonsense. They are run continuously because this is more energy efficient. However there is nothing stopping you from burning less coal. In France it is common to partially off nuclear power plants [wikipedia.org] during the night:

Nuclear plants do suffer from issues with throttled usage due to the nature of the fuel cycle. It's not that you can't throttle them, it's that as you get later in the fuel cycle it becomes harder and harder to throttle them quickly and keep them from being Xenon poisoned. Add to that the fact that our currently operating nuclear plants where not designed to throttle and you can understand why it's not a good idea. There is also the efficiency issue you cite, and with nuclear power plants running on thin margins to start, this can push them over the edge.

The primary thing to note is that it's basically hard to throttle most industrial sized power generators. Nuclear plants have longer lead times because changing power output of the nuclear core requires more engineering effort than a fossil fueled burner does which needs more effort than your hydro-electric plant. But it is *extremely* difficult to plan electrical power requirements far enough in advance to use our current 30 year old nuclear power plants which where designed to run for decades at static power outputs.

Add to that the fact that our currently operating nuclear plants where not designed to throttle and you can understand why it's not a good idea... Nuclear plants have longer lead times because changing power output of the nuclear core requires more engineering effort than a fossil fueled burner does which needs more effort than your hydro-electric plant. But it is *extremely* difficult to plan electrical power requirements far enough in advance to use our current 30 year old nuclear power plants which where designed to run for decades at static power outputs.

The biggest problem most countries using nuclear power have, is the plants that were built are now much older than they were originally designed to be. On top of that, many of these nuclear plants are using first generation nuclear technology. That is, technology developed not long after the second world war. These plants are inherently dangerous, and the Fukushima-Daichi nuclear disaster proved what can happen when something goes wrong. The thing is, it's not like we haven't developed much safer plant designs since, it's just that since incidents like three-mile island and chernobyl, many people have been against the building of new nuclear plants.To me, this seems crazy, because now many countries are trying to increase the operating life of some very old and unsafe reactors, where we could have built fresh new reactors, which are much safer, more energy efficient, and will most likely age much better. If the anti-nuclear protesters 20 years ago could have seen the impending peak oil crisis, and the global warming crisis, i'm pretty sure they would have shut up and we would have much safer, more flexible, and longer-lasting nuclear plants than the 30-40 year-old reactors many countries are still relying on today.

Actually, most are Gen II (if I recall correctly, Gen I was just research reactors). China has some Gen II+. There are also a bunch of Gen III+ reactors out there (I believe Gen III were also only research reactors and production moved to Gen III+). The US is just starting to build Gen III+, partially due to the regulatory snarl in getting them approved.

I'm fairly certain all Gen IV designs require passive safety, but the US abandoned development of these in the 1990s led by John Kerry, largely citing data that applied only to Gen II reactors and proliferation concerns (which is ludicrous - if you're that concerned about proliferation due to continuous reprocessing, make it closed loop and get roughly 80% efficiency of fuel instead of 99.5 and burn up the nations nuclear waste stockpile in the meantime - exactly what Russia is doing) . I'm sure we will be buying these from Russia in a few years, as they are the only country to have them approaching production (well, India is isn't terribly far behind, but the only other one I know of is Japan, and they've not been doing much in the nuclear space recently).

"TOTALLY UNSAFE! We'll walk it. Walking is safe." "But mom, it's 50 miles to where we have to go." "WALK."...

It's actually worse. It's like you're a business owner, and since you were hurt in a car, you don't purchase them anymore. But you can't do business without a car, so you keep using the cars that were in the fleet when you got hurt, even though at this point new cars would be an OOM safer. But NO NEW CARS!!!! means that you spend more money keeping the old unsafe beasts moving.

Actually that is not true either. The plants were in fact originally designed to load follow and were only later adapted to constant full power operation based on economic factors. It is not hard at all to engineer the plants to load follow. And xenon poisoning has nothing to do with it, the primary challenge is in axial offset control which becomes more difficult later in the cycle, but only because the cycles are optimized to run at constant full power with maximum fuel loading. It would only require modest adjustments typical of cycle-to-cycle operational changes to design to load follow. IAANE.

If our currently designed nuclear plants were not designed to throttle...maybe we should add that to the litany of reasons why we should be building new plants that might take into account some of the advances that have been made in the last 40 years.

I would agree. We need to allow new nuclear technology to be built and deployed in this country. However, the environmentalist lobby would have kittens and pretty much make that impossible should anybody actually *try*.

Sorry, gotta get the nimby's and the environmentalists to piss off first. Since they're the ones who throw a hissyfit every time someone wants to build one...and that of course includes safer and better designs.

Current nuclear power designs are based on the old designs which were designs to produce dangerous stuff meant to be used by the military. If they wanted a safe nuclear power option, they would have went with some of the other options. Safety and health was never a primary concern. Newer nuclear power designs have less nuclear waste than coal power plants.

Nuclear is inflexible. I think nuclear plant should produce hydrogen during low load period and that cars should run on hydrogen. In Germany, they have stopped using nuclear, the result is more pollution caused by coal. Il think nuclear is the less bad solution until solar solutions are developed.

Coal is inflexible too. The money needs to go into more renewables and into energy storage. All the necessary technology exists, it just needs building, and there is only so much money to go around which is one reason why we don't want it spent on nuclear.

The renewable generation of power tech exists, but we don't have any way to store base line grid power yet. The super simplified example, is night time. How are you going to store enough energy to power the US while it's dark?

That said, yes we need to be plowing money into renewables, it's an investment that will pay itself off many times over...but unfortunately over a number of decades and so private industry simply isn't going to do that.

"The renewable generation of power tech exists, but we don't have any way to store base line grid power yet. The super simplified example, is night time. How are you going to store enough energy to power the US while it's dark?"

Reactors can throttle about 10% on a daily basis. Night time loads are about 55% of daytime. So where are the reactors storing that power now?

Oh what , they don't do that? They actually use other forms of power to fill in?

Any links? I find it hard to believe you could do even 1/2 of base load grid power that way. Sure, 'technically' it's doable, but the reality of suitable sites for putting all that pumped stuff (I'm assuming water?) limits how much you can actually scale.

According to the wiki on Pumped-storage hydroelectricity (PSH), 'PSH accounts for more than 99% of bulk storage capacity worldwide: around 127,000MW, according to the Electric Power Research Institute (EPRI), the research arm of America's power utilities.' Since in pumping the size of the reservoir is not the limiting factor, but rather the throughput of the pumps, this means that PSH can be used to store the daily output of 127GW worth of power plants. Britain's consumption is 35.8GW on average, and 57.490GW at peak (http://en.wikipedia.org/wiki/Energy_in_the_United_Kingdom), so the global installed PSH's could easily absorb the UK's production.

In the UK, however, there seems to be only one plant (http://en.wikipedia.org/wiki/Dinorwig_Power_Station), costing 425M GBP in 1974 capable of absorbing around 1GW worth of power, so nowhere near 50% of base load, so it seems that PSH costs around 425M/1G = 0.5 pounds per watt capacity. Apparently, a new nuclear plant costs about US$ 5,339/kW., or 4 pounds per watt capacity, while windmills cost around 1-2 pounds per watt. So, assuming enough sites for PSH can be found, the costs for power storage capacity seems to be 5-25% of the cost for generation capacity.

According to the wiki, "The stalling of the UK nuclear power programme in the late 1980s and the coincident "dash for gas" increased the network's ability to respond to changes in demand, making the use of pumped storage for day/night load balancing less attractive. As a result, a similar facility planned for Exmoor was never built.[2]"; so it seems that at the time the demand is what limited PSH construction, not cost or environmental factors.

Short answer - In their fuel. They aren't storing any power at all, they are simply producing it. That's the difference between a power source that uses a physical 'fuel' and one that uses sunlight/wind.

Your example would work if the reactors only ran in the day time and then somehow that energy had to be stored for use at night as well. It isn't.

For other intermittent sources there are a number of options, including batteries. Some 200MW wind farms in Japan have 50MW backup batteries. When the wind is low (it never stops) the batteries smooth the output. They use sodium sulphur cells, easy to recycle and not damaging to the environment, heated with solar for extra efficiency. Even on an overcast day solar heating works at about 70% efficiency.

Wind varies from 0% capacity to 100% capacity minute by minute. It is not constant. There is also an upper limit to wind speed as turbines have to be stopped to prevent damage.

Solar thermal collectors would work well in the US and are 24/7 with constant,

They work well in the US south west. Most of the world does not have those kind of condition including the weather and ample free area. Sure the Sahara is similar but there seems to be some geopolitical issues with building there right now. Where are those conditions anywhere near Chi

This is an example of a false model of how the grid works. It appears that you believe that no matter where the electricity is injected into the grid it is immediately available to all users of the grid. This is the lake model of the grid. No matter where on the lake the electricity is injected it can be extracted anywhere else. This is a an inaccurate model. Am more accurate model is a canal system where the transmission lines are the waterways. Electricity can be injected into the canals but it has to be switched and transported through transmission lines. These lines have load limits and line loss. If there is a major storm in Norther Europe and the closest working turbines are in Spain the transmission line between Spain and Germany have to have the capacity to transmit all that power. Right now they do not and it is very expensive to put in such high capacity lines.

tke a look at this [fraunhofer.de] document. It is real data from the German electricity system. Look at the weekly charts starting on page 101. The green band is the wind generated power. Notice some days there is a lot (jan 3) while other days there is almost none (jan 12). Wind power is not consistent

From that same report Germany had 32.5GW of installed wind power and produced a total of 47.2 TWh of electricity. If the turbines produced 100% capacity they could have produced 284.7 TWh but they only produced 11% of that.

Geothermal requires two things to be together; heat and water. If you drill deep enough heat is everywhere. The water is a bigger issue. The water has to be quite pure as impurities will gum up the works. Diverting massive amounts of potable water to generating electricity is a non-starter as we already have potable water shortages. Depth may also be an issue as the further you go down the further the water has to come back and it will cool on the way. Those are some of the reasons why geothermal is only vi

Coal is inflexible too. The money needs to go into more renewables and into energy storage. All the necessary technology exists, it just needs building, and there is only so much money to go around which is one reason why we don't want it spent on nuclear.

Meh, all that crap will take to long. In just a few short years our species will consume more energy than we can produce with all of those combined. So not only is the sum of them insufficient, the pollution involved in mining and harvesting the resources, construction of the facilities, all the infrastructure, and so on will destroy the planet just as part of the opportunity cost.

We need to cut our losses, start researching and building generational spaceships, and roll out the lottery to find the lucky f

You use the wind power to run the pumps on reservoir storage, or to electrolyze water to run Sabatier reactors which generate hydrocarbon gases like methane. Feed the hydrocarbon gases into the existing natural gas pipelines which feed the gas turbine peaking plants. The natural gas pipeline system can maintain at least several days worth of supply for the whole nation.

There are more ways, those two are my favorite candidates. Just keep T. Boone Pickens away from the natural gas.

Reservoir storage costs money, about $200 million per GWh assuming good geography for the high and low reservoirs and lots of surplus water (a major problem for large drought-ridden parts of the US and other countries). Pumped-storage wastes about 30% of the electricity fed into it, for every GWh put in it can put out 650MWh on demand. Sabatier reactors and other electrochemical cells have poor conversion efficiency and cost money to build and operate so the round-trip efficiency of electricity in to electr

I think nuclear plant should produce hydrogen during low load period and that cars should run on hydrogen.

Hydrogen powered cars face huge technological and economic hurdles with no solutions on the horizon. Unless there are unforeseen breakthroughs, the car of the future is going to be powered by electric batteries, not hydrogen. Besides, electricity-to-hydrogen-back-to-electricity has a round trip efficiency of less than 50%.

In Germany, they have stopped using nuclear, the result is more pollution caused by coal.

Germany is a classic example of idiotic and counter-productive policies driven by environmentalism run amok. There are some good arguments against building new nukes. But it is insane to shutdown existing nukes. Their solar energy mandates are another example of bad policy: they have resulted in a large percentage of the world's solar panels being installed in one of the cloudiest places on earth, rather than where they actually make sense.

The Green Party in Germany has had a taste of political power, and like most idealists, they have abandoned their ideals in pursuit of more power. So they engage in sound-bite politics and propose simplistic solutions to complex problems. The environment suffers, but hey, their poll numbers to up!

Come on, there have been a ton of advances around storing hydrogen, and building fuel cells generally - also around extracting Hydrogen.

Not enough to base our infrastructure on those advances. Hydrogen powered cars face three obstacles - one technological and two economic. The teachnological one is developing a functioning technology. There are hurdles to overcome but there is reason to believe they could be overcome. After all, fuel cells and the like are already in existence and prototype vehicles have been made. The much bigger problem is economic. The first economic problem is that hydrogen powered cars are expensive because there is no manufacturing economies of scale, supporting industries and a limited manufacturing base. Absent some sort of subsidy they cannot be produced for a price in the near term that is competitive with existing vehicles. The second economic problem and the real killer is that there is no fuel infrastructure in place and developing one would be hugely expensive. We have infrastructure in place for natural gas, petroleum/diesel products and electricity. Anything that doesn't use one of those three things is essentially starting from scratch.

The truth is that if you want every person to own an electric car, Hydrogen is the only way you get there.

Not even remotely. Hybrids are the path of least resistance (no pun intended) towards electric vehicles. Electric vehicles based on batteries become practical once you solve the charging time problem. Basically you have to get charging time down below about 10 minutes for at least 200 miles of range. We're almost there technologically already.

You cannot manufacture a literal ton of batteries per person across the globe

Actually you probably can. Every vehicle made already has at least one battery in it and it wouldn't be all that complicated to scale up production unless there is some sort of raw material limitation.

There's a simpler way of looking at the electric car conundrum. Of all the energy used in the industrialized world, about half is used for transportation in the form of oil. In order to replace all cars with electrics, we would have to literally double all electric generation and transmission capability. No small undertaking.

Of all the energy used in the industrialized world, about half is used for transportation in the form of oil. In order to replace all cars with electrics, we would have to literally double all electric generation and transmission capability

Not all "transportation" is cars, by quite a long shot. Trains, planes, ships, semis, etc. We can switch all cars to electricity while those continue to burn oil (or natural gas), and then figure their futures out, later.

Hydrogen is actually a terrible solution for cars for a number of reasons.

1. Creating hydrogen from water is very inefficient and prohibitively expensive for transportation.2. Creating hydrogen from natural gas is at best around 70% efficient due to the laws of physics, then there's all that CO2 left over.3. Compressing hydrogen consumes at least 20% of the energy contained in the hydrogen. Cryogenically cooling it is far more energy intensive.4. Fuel cells such as the type used in cars are at best around 40% efficient. Fuel cells also must maintain a certain temperature range, even when not in use. They must never freeze or they will be destroyed. They also must maintain a certain internal humidity level.5. Transportation of hydrogen is expensive. For pressurized hydrogen the tanks are quite heavy. A truck carrying enough hydrogen for around 200 cars will weigh around 13 tons due to the tanks.6. Existing pipelines cannot be used. Hydrogen embrittles metal so the pipes must be specially lined.7. Safety is a concern for refueling. The Alameda County hydrogen filling station for the fuel cell busses already had one fire due to a failed valve and this refueling station is not open to the public.8. Hydrogen is extremely flammable and burns with an almost invisible flame. A hydrogen leak in an indoor area could be catestrophic. Hydrogen also will leak through virtually any joint. Hydrogen is also explosive over a very wide range of mixtures with air, more so than even natural gas.9. A diesel powered car is more efficient than a hydrogen fuel cell and will produce less CO2 since virtually all hydrogen comes from cracking methane.

In the short term anyway. Variable sources need a method to store the energy for when the supply is low. This is the biggest thing holding back renewables right now.

In regards to climate, nuclear is the only viable option (and I *hate* nuclear!) going forward until we have new technology that stores energy more densely, more efficiently and cheaper than is available today.

A wild guess is probably 100 years or so before we can truly move to renewable sources only, for base line grid power.

Well, you are wrong.We are talking about very very high voltage DC.AC loses energy by radiation and by inducing low currents into nearby conductors, DC does not. That is why modern long range lines are DC.

Yes, that is why nuclear powered ships and subs have to boil the ocean, clouding port cities with steam whenever they want to stop... no wait, they don't. They just turn down their variable output. Nuclear is the perfect partner power generation to renewable.

They can simply lower the control rods in the reactor when the sun is shining or the wind is blowing:

Until fusion is everywhere, not one single energy source can serve our needs:

1: Thorium fission reactors need a look at. Yes, there have been working ones, almost 40 years ago. Cheap, effective, scalable, and a lot of energy in a relatively small chunk of real estate.

2: We need energy dense batteries. We have come a long way, but things will change big time when we start getting within an order of magnitude of gasoline for energy stored per volume. When this happens, car engines can be tossed for electric motors.

3: With all the advances in solar, from window tint PV panels to cheap panels for large surfaces, to high efficiency panels to get the best bang per buck out of small areas (RV rooftops), solar is a "why not?", rather than a "why?". The best use would be hybrid systems that can charge batteries, and when the batteries are charged, then feed the grid. That way, one is guaranteed very clean power on the circuits the batteries feed (assuming a quality inverter.) Solar is a must have for virtually any installation.

So, hook the nuclear power plant up to batteries, a flywheel, or pump some water uphill for hydroelectric when needed. Or shit, just provision for maximum capacity and release waste heat when it's not all needed. This is not a serious practical objection to nuclear power.

Its bullshit. The French vary their reactor power output from 30% to 100% capacity and they can vary output by 5% per minute. Nuclear does not have any problem coping with load demands from daytime to nighttime. How did you think the French handled the loads to begin with when over half of their production was nuclear?

The problem is having power on demand. I want to turn on the heating *now* now wait until the wind blows of the sun shines. If I could wait until the sun shined I wouldn't need heating to begin with. Duh.

France uses their nuclear plants for load-following: they can ramp up/down their nuclear plants at about 5% per minute. That means that you only need to back your wind/solar with a few minutes worth of battery capacity to work in tandem with the nuclear plants.

Also, hippies don't compromise. Once they have it in their head that solar and wind are the way to go, then those are the ONLY way to go and YOU MUST DO IT THAT WAY AND NO OTHER WAY!!!!!!! No amount of reasoning will sell them on hydroelectric, nuclear, or natural gas (even pointing out that they're all much better for reducing CO2 than continuing with coal).

For environmentalists, it's not about taking reasonable steps, making reasonable compromises, working together, etc. It's about a cause. And the best causes for them are the ones that they can't win, allowing them to relish in the warmth of perpetual self-righteous victimhood.

That is exactly the problem. The article makes it seem as if pro-nuclear and greenie types are attacking each other. In fact, the attacks are entirely in one direction: from the greenies, toward nuclear power. I don't see many pro-nuclear people protesting the construction of new wind farms. Nor do pro-nuclear people attack solar power. Usually, pro-nuclear people are comfortable with both nuclear and renewables, and want both.

The greenies insist that power generation must be renewable only, and if they don't get exactly that, then they'd rather just burn coal and have global warming (witness Germany).

From the article:

Meanwhile, it’s time to stop wasting ammunition on friendly fire. If activists care about the climate as much as they say they do, they should focus on their areas of agreement, rather than their differences.

But greenies obviously do not care about the climate as much as they say they do. It's not among their top priorities. Their first priority is shutting down nuclear power even if that makes climate change worse (witness Germany). Their second priority usually is making sure that food is grown without fertilizer (??). Climate change is usually about their 10th environmental priority, to be sacrificed for any higher priority.

In California, where I live, greenies protest the construction of new solar power plants. Apparently, solar power plants would ruin the desert. Just solar power isn't good enough. It must be solar power exactly where they want it (apparently not in the desert?), or it's just back to burning fossil fuels.

It actually wouldn't surprise me to find that the coal industry was secretly funding some of the more extreme environmental groups. Every time one of them gets on TV and starts in with the "My way or the highway!" routine, it alienates more and more regular people, thus protecting the status quo. If the face of environmentalism were a reasonable person saying "Here's a plan. It's not perfect, and there are some compromises, but it's a big step forward," instead of some hemp-shirt wearing dude with dreads holding a sign protesting *everything*, then the public might actually get on board.

Wind and solar have variable output, so they need to be partnered with flexible power generation. Nuclear is fundamentally inflexible because you can't quickly ramp up or down electricity output from a nuclear power plant.

Wrong. Nuclear power can load follow (ramp up and down rapidly to meet instantaneous demand) perfectly fine. They just typically do not because they are large baseload plants and there is no reason to run them anything lower than 100% when you need fossil fuel plants to make up the difference. IAANE.

Wind and solar have variable output, so they need to be partnered with flexible power generation.

Another option is to partner variable output with consumption that can tolerate the variation.

For example, a nitrogen fixation plant based on the Haber process [wikipedia.org]. Fertilizer from this process is responsible for about 1/3 of Earth's food production, and uses 3-5% of our natural gas supply (some for raw Hydrogen, some burned to generate electricity on-site).

Instead of letting excess energy generation lay fallow, we could route the excess into ad-hoc, non-demand-generated production. For fixing Nitrogen, you cou

Nuclear output is not varied for practical reasons, not fundamental limitation.

All current grids with nuclear also have fossil fuels. When demand drops you turn the fossil fuels down, because that saves fuel and fuel dominates the cost of fossil fuel power generation. If you turn the nuclear plant down you don't save any money, costs in nuclear power are dominated by construction, other costs are pretty much independent over whether you are generating power or not.

Your statement is false and shows a lack of knowledge of nuclear reactor design and operation.

It is quite easy to ramp up electrical output from a nuclear power plant. A good example if a nuclear powered ship or submarine, both of which need to be able to accelerate quickly. Both use electric motors to turn the screws which move the vessel through the water. The electricity is provided via generators connected to steam turbines which are fed steam provided by steam generators heated by the nuclear reactors.

If more electricity is needed, increase the steam flow and the power output of the plant. The stored heat in the reactor coolant maintains the steam output while the reactor ramps up heat production.

If less electricity is needed, decrease the steam flow and the power output of the plant. The excess heat is stored in the reactor coolant as increased heat and pressure. This can be bled off by running the reactor at a lower power level.

If you are wondering how I know this, it is because I have actually training in nuclear reactor plant design and operation.

1) No. Wind and solar vary with clouds and wind patterns and have no correlation to usage patterns. Renewables do not cut into anyone's profits, only natural gas does that with massive oversupply with lack of storage/transmission capability. In fact, renewables tend to be big profit cash cows for industries because of government subsidies that pay for them to build them, even when and where they don't work, and then they get to write off the losses from taxes. W

were already building hydropower capacity to store the excess from the so-called "baseload" nuclear

Because it was more energy efficient to do it than having to throttle them up and down all the time.

An expansion of nuclear energy is likely to spread militarism

Bunk. Belgium and Switzerland have nuclear reactors. How many wars has Switzerland been in the last several hundred years? As for Belgium is mostly remember it being invaded rather than them invading anyone. What you are saying is similar to the adage that people can't make war without having steel so why not confiscate pots and pans to prevent people shooting each other. Its bunk.

How do you get backers for new nuclear power plants when massive cost overruns are the rule rather than the exception

If they were subsidized up the wazoo with guaranteed energy prices for 20-30 years after installation like wind is you can bet they would be installing them right now. If the US could build a nation wide railroad system with similar promises why do you think a couple dozen nuclear power plants would be any different?

Not necessarily. Read the report. It's more like the enemy of my enemy is my friend.

Nonetheless, one source is largely renewable and works from small to large scales, recycles its parts fairly well, and is a store-and-forward technology. The other has onerous disposal problems, and a vicious amount of potential vulnerabilities.

Perhaps one day, spent nuclear fuel could be repurposed and made harmless, but not today. And with rotten designs and poor oversight, nuclear power represents great danger to the envi

And so you didn't read it. Paying for a report doesn't pay for its bias, although it could. You could find out by climbing into what's being said. A healthy skepticism is required, of course.

Funded science occurs all the time, and it doesn't necessarily buy results. Certainly bad results often are buried, but this is more about joining forces, rather than projection or statistical nonesence. That said, I don't believe that nuclear development at this time is a good idea no matter the crux of their science,

Do you have an opinion on thorium salt reactors or other up and coming nuclear power techniques? Do they all have the same sort of problem you are talking about? I keep planning to read up on this more, seriously wondering if you've done so and formed an opinion.

Thorium salt reactors are still "up-and-coming" techniques. Although there have been a small smattering of experiments over time, the only significant testing of the idea was back in the '60s (the Molten Salt Reactor Experiment at Oak Ridge Nation Labs). Although most of the technical hurdles appear to be known, I don't think there is doubt that more work needs to be done to make this production worthy. Some of the biggest issues (e.g, metalugical radiation brittling and salt reprocessing efficiency), are hard to do small scale experiments with so the only real course is to build more experimental reactors to help understand this. Experiments like this are really expensive. The FUJI project (one recent attempt considered to be a leading effort) failed to raise $300M required to build their experimental miniFUJI reactor back in 2011.

There are also secondary effects that are unknown. Uranium mining of past decades created some pretty bad ecological damage and it is unclear that Thorium minining would be any better (or be similarly econonmical with lower impact mining techniques). There is also the issue with decommissioning (even with existing Light-water reactors, this is an ongoing cost concern). At Thorium Salt Reactor have greater fuel efficiency...

One of the continuous knocks against Thorium Salt Reactors has also been nuclear proliferation security issues with reprocessing (since the most efficient configuration for Thorium Salt Reactors is a breeder configuration), but although there are some known safeguards available for denaturing to make bomb-capable material difficult to extract, terrorist level dirty-bomb material is always available in large quantities (a different threat model than in the 60's)...

Nucelar power has problems and if we were to use it as much as we use fossil fuels, it would cause the same problem.

No. Look around. Not every nation have the same setup as United States.It has nothing to do with what is most efficient or what works, it is all politics. Going mostly or all nuclear is completely viable, you have just decided not to. (Or rather abstained to make a decision.)

Have a look at Norway for example, they have 99% hydroelectric. Yes, it has its own problems with area used for dams and such but you can go 50/50 hydroelectric and nuclear or 25/75 or whatever you fancy. The interesting thing with hydr

However, I do want nuclear power advocates to get away from pressurized light water reactors (PWR's). There are so many disadvantages to using PWR's, especially with the use of expensive uranium-235 as fuel and the dangers of using a pressurized reactor vessel.

Meanwhile, China and DARPA are working on a joint experiment to test scaling up the molten-salt reactor (MSR) design that was successfully tested for nearly a decade at Oak Ridge National Laboratory. If they can scale it up, that means we'll have a n

Actually, at least in the United States, all the rivers that can be used for hydro electric are being used for hydro power.

What we need to do is get over "proliferation" and rewrite some of the damn treaties to allow the reprocessing of spent fuel as well as change our reactor designs over to ones that will burn the spent fuel. I know the Thorium cycle reactors are a lifetime away, for me anyway, from being commercially ready. But you burn up all those bombs and spent fuel rods already created over the ne

> Nucelar power has problems and if we were to use it as much as we use fossil fuels, it would cause the same problem.

Nuclear's problems are vastly exaggerated. There are industrial accidents and oil and gas explosions every week that have more fatalities than the Fukushima disaster. Passive safety features in modern designs make them safer still, and that's before fancy designs like subcritical reactors. There are methods of destroying nuclear waste (transmutation) or using it as fuel. People worry abou

You can only claim a plant is a net consumer of carbon if over it's entire life-cycle it consumes more than it produces.

After a plant dies it decomposes and releases the CO2 back into the atmosphere - unless it gets trapped in situations that produced our oil. But that's a different case. In 'normal' conditions, they consume and then release CO2.

likewise people. We consume carbon through eating and release it through breathing and other outputs

The rebuttal loses me with this line:"Nuclear power plants (large or small) and renewables are not compatible technologies. A distributed grid design with high penetrations of variable renewables requires flexible technologies for balancing the system. Both nuclear and coal plants are inflexible. "Maybe they don't get what people mean by "flexible" in regards to the grid?When people say coal and nuclear are flexible, they don't mean you can move the plant, or install and remove plants at will. What they mean is that the energy production can ramp up quickly when 15,000 people all get home from work and cut their AC on at the same moment...yes renewable sources are improving how they can scale and ramp up.

Nukes are already there. I'm also annoyed at how articles claim normal tax items (vehicle fleet depreciation, etc) as subsidies for one industry, but then say industry X doesn't get subsidies. EVERYONE gets some form of tax breaks when you fill out your taxes. If you don't claim them, well, then that's on you.

The original article is right. We SHOULD push for more nukes as well as more renewable sources. Getting off of coal / diesel should be the first priority. Eventually if we can wean from nuclear? cool...

Getting off of coal / diesel should be the first priority. Eventually if we can wean from nuclear? cool...

This pretty much sums it all up.

Now if only the idiots who're insisting we go whole-hog for energy solutions that WON'T cover all our contingencies would shut the hell up and get out of their own way, we could start working towards this end.

Renewables may have scaled up already too much in some countries... In January, wholesale prices for electricity in Germany & Nordic countries were negative for a brief period when the January storms sent wind & hydro production up... http://www.reuters.com/article... [reuters.com]

Nuclear needs to be a "backup option", but it needs to be always on. What do you do, however, when renewables (solar, wind, etc.) are flooding the grid, but with production that could disappear completely with a weather change in a

Half the people arguing on behalf of anything should probably shut up about it. There are legitimate arguments for and against solar and nuclear, and I used to really enjoy debating them (hypothetically, what if the government spent the equivalent of R&D on anything besides nuclear?) But these days most "advocates" just bog down the dialectic.

Take for example the perfectly logical argument in favor of allowing the Keystone pipeline... If you don't build the pipeline, it gets built anyway, and you h

Ask Michigan how the cleanup in the Kalamazoo river is going. Unlike 'normal' oil most people are familiar with, heavy crude/tar sand oil sinks in water and cleanup is ridiculously expensive and hard and you don't really ever get your environment back to normal.

As for the arguments 'for' the pipeline, many of the supporters claim we'll get the refined oil produced. That's wholly untrue. It goes on the market and is up for anybody to buy. It would likely not make much of a

Solar/wind/hydro/etc. are "relatively" clean and may be "literally" non-polluting once the plant is built, but they rarely have anything close to zero ecological impact.

One nearly-inherent aspect of renewables is that they won't "run out" like fossil fuels and uranium. Some carbon-based fuels, such as burning fast-growing plants, are "renewable" in this sense but are far from pollution-free.

Uranium "running out" is hundreds or a thousand years away -- assuming we abandon the insanely wasteful "Once through and throw most of the fuel away" cycle. That doesn't count extracting uranium from sea water, which the Japanese demonstrated back in the 70s could be done with an ion exchange process for a few hundred dollars a pound in 1970s dollars. And then there's thorium...

The omni-obstructionists and the arithmetic denialists oppose any energy source -- that's any energy source -- that risks allowi

Actually France has some major problems. Apart from a string of low level but concerning accidents over the years they suffered from power cuts when the weather got too warm for the plants to operate. At first they tried dumping hot water into lakes, killing much of the wildlife living there, but had to stop and just idled the plants instead.

The only thing that saves them now is being able to import energy from other countries, particularly Germany where it gets very cheap during warn periods.

Being reliant on a single source of electricity is a really, really bad idea. One of the biggest strengths of renewables is their diversity and distributed nature. People actually died in France due to those shut downs.

The nuclear industry seems a lot like the American automotive industry, and maybe for good reasons. They've had to fight political battles and prove themselves against fossil fuels in and early on people were not concerned with global warming.

I know there are prototype "meltdown proof" reactors but why aren't they the norm? Anything to do with output and cost? Fukushima's best plan now is to freeze the ground for I don't know how many years? It's going to cost half a billion dollars to build the system

They're not reasonable. You can't strike any sort of deal with them on any sort of rational basis.

Here are your options.

1. Over power them politically. This is politically expensive and is pretty annoying because they won't shut up which will mean you'll have to sustain a pretty high level of political suppression for some time to come.

2. Simply confuse them. They're by definition not very observant. They track on things put in the newspaper recently and don't really follow the logic of anything through. So

I'd just like to know the world I hand down to my children and grandchildren doesn't include stories about "those funny switches on the wall which don't do anything." Because that's the road we are on.

See, that dystopian future just won't happen. We're not going to just wake up one day and find that there's no coal left in the ground, and whoopsie, we can't power the world anymore! It's an asymptote, not a brick wall. Coal reserves are going to disappear slowly, and new coal will be harder to find and more expensive to mine. So the price of coal will rise, gradually. And just as gradually, people will start getting power from sources that used to be more expensive than coal, but aren't anymore since

Its a building. Its build using stuff used to make buildings. It could have been brick if you wanted to. Lets stop making buildings because they pollute too.

energy used in the mining, extraction and refining processes

Yes because solar panels and windmills aren't made of materials which need mining operations. Silicon wafers are magically turned with no energy from what is essentially silica sand into crystal ingots. Not.